stewart



s. 8. WEEKS AND 0. n. SIEWABT. FURNACE DRAFT REGULATOR- APPLICATIUNFILED DEC-18. 1916' 1,3 14, 1 74. Patented Aug. 26, 1919.

2 SHEETS-SHEET I.

INVENTOR SHfRLEY 5. WEEKS CARLTON D. STEWART S. 3. WEEKS AND C. D.STEWART.

FURNACE DRAFT REGULATOR.

APPLICATION FILED 02c. 18. ms.

Pamnted Aug. 26, 1919.

2 SHEETS-SREET 2- SHIRLE Y 8. WE EKS CARLTON D. ST E WART UNITED STATESPATENT OFFICE.

SHIRLEY S. WEEKS, F OAKLAND, AND CARLTON D. STEWART, OF BERKELEY,

CALIFORNIA, ASSIGNORS TO ASSOCIATED ENGINEERING AND SUPPLY COM- PANY, OFSAN FRANCISCO, CALIFORNIA, A CORPORATION OF CALIFORNIA.

FURNACE DRAFT-REGULATOR.

Specification of Letters Patent.

Patented Aug. 26, 1919.

Be it known that we, SHIRLEY S. WnnKs and CARLTON D. STEWART, citizensof the United States, residing at, respectively, To all whom it mayconcern: Oakland and Berkeley, in the county of Alameda and State ofCalifornia, have jointly invented a certain new and useful Improvementin Furnace Draft-Regulators, of which the following is a specification.

This invention relates to fuel oil and gas burning apparatus, and moreparticularly to automatic controlling mechanism therefor.

The principal object of our invention is to provide means for insuringthat the dampers will be open when fuel is admitted to the furnace andclosed when fuel is out off from the furnace so that the dampers willalways be in the proper position to safely and economicall control thefires.

Other objects and a vanta s will appear in the following more detaieddescription of the invention.

In the accompanying drawings; Figure 1 is a front elevation, partlybroken away, of one of a batter of steam boilers, with our improvedliqui fuel and furnace draft regulating apparatus applied thereto; Fig.2 a side elevation of the furnace draft regulating mechanism shown inFig. 1, with certain parts omitted; Fig. 3 a detail View of the strokeadjusting device for the furnace draft regulator; Fi 4a centralsectional view of the control ing valve and p-islzon-mechat nism of thedraft regulator; Fig. 5 a central sectional view of the one unit of themaster controller; Fi 6 a transverse sectionv on the line 'a-c of i 5;Fig. 7 a central sectional view of t e fuel regulator; and Fig. 8 asection on the line Zi-b of Fig. 7.,

In Fi 1 of the drawings, there is shown a steam iler 1, partly brokenaway, having a steam dome 2, a stack damper 8, ash pit or draft doors 4and provided with oil or gas burners 5 of any desired construction.

The regulating apparatus inaycomprise a master controller having two ormore controller units 6, 6', each connected to a. steam supply pipe 7,fuel and atomizing regulators 8, a fuel pump 9, and a furnace draftregulator having two or more regulating units 10, 10.

Each master controller unit 6 may comprise a casing having a chambercontaining a piston having differential piston heads 11 and 12. Pistonchamber 13 containing the small piston head 11 is connected to pipe 14into which the pump 9 supplies liquid fuel under pressure and pistonhead 12 is contained in piston chamber 15 the pressure in which iscontrolled by a valve 16.

The annular chamber 17 intermediate piston heads 11 and 12 is connectedat one side to pipe 18, through which fuel udder pressure is supplied tothe fuel regulators 8 and the draft regulators 10, and said chamber isalso connected to an overflow or return pipe 19.

The valve 16 is controlled 'by a diaphragm 20 connected thereto by rod21 and subject on one side to the pressureof an adjustable spring 22 andon the opposite side to steam pressure supplied from the boiler throughpipe 7. v

be fuel and atomizing agent regulator 8 may comprise a casing havingpiston chamhere 23 and 24 containing pistons 25 and 26 subjectrespectively to the pressure of springs 27 and 28 and connected to pipes29 ?.{)Id 30 leading to the draft regulators Steam for atomizing theliquid fuel is supplied through pipe, 31, and admission through pipe 32to' the burners 5 is controlled by valves 33 and 34:. Fuel is suppliedto the regulator through pipe 35 and communication frompipe 35 to pipe36 leading to the burners 5-is controlled by valves 37 and 38, liquidfuel being supplied to pi e 35 by the pump 9 through a. reducing va vs39. i p

. Each of the draft regulating units 10 may comprise a casing having apiston chamber 40 containing a piston 41 carrying a piston rod 42 and avalve chamber containing a piston valve 43 having a stem 44 adapted toengage the piston 41. i

The piston chamber at one side of the piston 41 is. connected to thereturn pipe 19 and the piston chamber at the opposite side is connectedto ipe 18.

The piston ro s 42 are connected to other by a chain 45 which passesover a pul ey 46 and the pulley is secured to one end of a rod 47, theopposite end of which is connected to a lever 48, as more clearly shownin Fig. 2 of the drawings. The lever 48 is secured to a shaft 49carrying at its opposite end a lever 50 which is connected by a rod 51with a lever 52 adapted to operate the stack damper, 3 the stack damperbeing provided with a weighted arm 53 tending to turn the damper to itsopen position.

The pulley 46 also carries a downwardly proj-ecti rod 54 which isconnected to the end of a ever 55, secured to a shaft 56. To the shaft56 is also secured a lever 57 connectedby a rod 58 with a, lever 59 foroperating the 'ashpit door 4 and a weighted lever 60 is carried by shaft56 and tends to throw the door 4 open.

In order to limit, and provide for the adjustment of, the stroke of thepistons 41 to correspond with the movement necessary to operate thedampers, adjustable stops 61 adapted to be clamped to the chain 45 arerovided, as shown in detail in Fig. 3 of Fire drawings. The stops 61upon engagement with the upper ends of casing 62 prevent furthermovement of the pistons 41, as will be evident.

In operation, fuel under pressure is supplied by pump 9 through pipe 35,at a reduoed pressure corresponding with the adjustment of reducingvalve 39, to the regulators 8, so that the upper faces of pistons 25 and26 are sub'ected to fuel'under pressure.

Fuel under the full pressure of the ump also passes through pipe 14 topiston c amber 13 of each master controller unit 6 and to the ressurechamber 63 of the damper control ing device 10, 10.

Steam pressure from the boiler is admit ted through pipe 7 to the up orsides of diaphragnis 20 and is supplied t rough pipe 31 to theregulators8.

Assuming the iires in the furnaces to be burning, the dampers, open, andthe springs 22 adjusted to the desired stearn pressure, for example, thespring of the unit 6' may be adjusted to the maximum steam pressuredesired whiie the spring 22 of the unit 6 may be adjusted to within twopounds or less of the maximum boiler pressure.

The valve 16 being closed, fuel under pressure flows from piston chamber13 through a restricted passage 64 to piston chamber 15 and since thepiston head 12 has a greater area than'piston head 11, the differentialpiston device will be shifted to its lower posltion, in which the pipe18 is connected by the annular chamber 17 with return pipe 19.

When the steam pressure rises to a degree slightly exceeding thepressure of s ring 22 in a master controllerunit 6, the

iaphragm 20 will move downwardly and through stem 21 will cause valve 16to be opened. 7

The fuel under pressure in chamber 15 is then vented through passage 65to return pipe 19 at a greater rate than it can flow through restrictedpassage 64 and consequently the higher pressure acting on piston head 11operates to shift the diiferential piston device to its upper position,in which the piston head 11 closes communication from pipe 18 to thereturn pipe 19 and opens communication from supply pipe 14 to pipe 18.

Fuel under pressure is therefore supplied through pipe 18 to the u perface of piston 41 of the damper regu ator unit 10 and thence throughpassage 66 to pipe 30 which leads to the piston c amber 24 of the fuelregulator 8. Since the fuel acting, above the piston 26 is at a reducedpressure, the full pump pressure of fuel now admitted below the iston 26operates to shift same to close the uel and atomizin agent supply valves38 and 34, so that on y the valves 37 and 33 remain open andconsequently the fuel flow is reduced and the intensity of the fire inthe furnace is diminished.

The piston chamber 40 being open to the return pipe 19, the fuelpressure acting on the upper face of piston 41 of unit 10 causes thepiston to move downwardly so as to cause a downward movement of thepulley 4'6 and rod 47. The stack damper is thus turned to partiallyclose the sam'e as shown in Fig. 2 of the drawings and similarly thedownward movement of the rod 54 operates to partially close the ash pitdoor 4, the movement being limited by the engagement of stop 61 Withcasing 62.

' When the piston 41 is in its uppermost position, a port 67 permitsflow of fuel under ressure from pipe 18 and around the loosely tted stem42 to the chamber above the piston valve 43, so that the fluid pressureson opposite sides of the piston valve being baianced,'the spring'68 willforce the same downwardly as the piston 41 moves down.

As thepiston valve 43 moves downwardly, it closes communication frompipe 1 8 to pipe 30, but by "the same movement, communication is o enedfrom the chamber 68, containing fue under full pum pressure through theannular chamber of the piston valve to pipe 30, so that the maximum pumpressure is maintained on the piston 26 of tllie'r'ggulator 8 to hold thefuel supply va lves c ose the furnace fires partially reduced and thedampers artly closed by the above operation s oui there be a furtherincrease in boiler steam pressure suiiicient to overcome the pressure ofthe sprin 22 of the master controllerunit 6, then t e diaphragm 20 ofthis unit will operate to open the valve 16 so as to vent fuel underpressure from piston chamber 15 thereby permitting the fuel pressureacting in piston chamber 13 on the piston head 11 to effect the movementof the differential piston 12, so that fuel under pressure is admittedfrom fuel supply pipe 14 through pipe 18 to piston 41 of the damperregulating unit 10'. Fuel under pressure is thereupon supplied firstfrom pipe 18 and then from chamber 63 to pipe 29 and thence to piston 25of the fuel regulator 8, operating the iston to close the valves 37 and33, thus cutting off the flow of fuel and atomizing agent to theburners, so that the intensity of the furnace fires is further reduced.

. The piston 41 of the damper regulating unit 10 is then actuated by thefuel under pressure so as to effect the downward movement of the stem42. The pulley 46 is thereupon shifted downwardly and causes the furtherclosing of the stack damper 3 and the ash pit door 4.

As in the operation of the damper controlling unit 10, the piston valve43 of unit 10 is shifted upon the downward movement of piston 41 so asto connect chamber 63 with pipe 29 and thus maintain full pressure onthe piston 25 of the fuel regulator 8.

While the maximum boiler pressure is maintained, the fire in the furnaceremains reduced and the dampers and ash pit doors remain closed thedesired amount. If the boiler pressure should reduce below the maximumpressure, the dia hragm 20 of the master controller unit 6 W111 be movedupwardly by its spring 22 closing the valve 16. This permits t eequalization of fuel pressures on the opposite piston heads of thedifferential piston device, so that the pressure acting on the largerarea of piston 12 causes the downward movement of the piston device,thus closing communication from pipe 18' to supply pipe 14 and openingcommunication from the pipe 18' to the return pipe 19.

Fuelunder pressure is then vented from piston 41 of the damperregulating unit 10 and the counterweights 53 and 60 cause the stackdamper 3 and the ash pit door 4 to open, the piston 41 moving upwardly.

While the piston 41 is moving upwardly to open the dampers, the pistonvalve 43 remains in its lower position until the piston 41 has nearlycompleted its upward stroke, when the same engages the piston valve andshifts same upwardly. The upward movement of the piston valve 43 thenconnects pipe 29 with pipe 18', so that the fuel under pressure inpiston chamber 23 is vented, permitting the fuel pressure above thepiston 25 to shift same and open the fuel valve 37 and the atomizingagent valve 33 and thus increasing the fuel supply to the burners.

In a similar manner, if the boiler pressure should still further reduce,the diaphragm 20 of the master controller unit 6 will be moved upwardlyby its spring 22, closing the corresponding valve 16 and therebyeffecting the furt er opening of the stack damper and the ash pit door.When the piston 41 of the unit 10 engages the piston valve 43 in itsupward movement, the fuel ressure is vented from piston 26 of the uelregulator through pipe 30, so that the valves 38 and 34 are opened tostill further increase the fuel supply to the burners.

It will now be evident that in the operation of our construction theopening of the dam ers is positively assured when fuel is admitted tothe burners, and the dampers are closed the desired amount when the fuelsupply is reduced.

Any desired number of fuel regulators 8 and damper controllers 10, 10'may be governed by the master controller, and if desired, additionalmaster controller units may be employed in order to provide an increasednumber of steps in the regulation.

Having now described our invention, what we claim as new and desire tosecure by Letters Patent, is:

1. In a liquid fuel burning apparatus, the combination with a furnaceand a mechanism for regulating the flow of fuel to the furnace, of adevice for regulating the furnace draft and means operated by Saiddevice after the furnace draft has been opened for effecting theoperation of said mechanism to increase the supply of fuel to thefurnace.

2. In a liquid fuel burning apparatus, the combination with a furnaceand a mechanism for regulating the flow of fuel to the furnace, of adevice for regulating the furnace draft and means operated by saiddevice before the furnace draft has been closed for effecting theoperation of said mechanism to reduce the supply of fuel to the furnace.

3. In a liquid fuel burning apparatus, the combination with a furnaceand a mechanism for regulating the flow of fuel to the furnace, of adevice for regulating the furnace draft and means operated by saiddevice for effecting the operation of said mechanism to vary the supplyof fuel to the furnace.

4. In a liquid fuel burning apparatus, the combination with a fuelburner and a fuel regulator operated by fuel under pressure forcontrolling the suppl of fuel to the burner, of a damper regu atoroperated by fuel under ressure for controlling the flow of fuel un orpressure for operating said fuel regulator.

5. In a liquid fuel burning apparatus, the combination with a fuelburner, a fuel regulator operated by fuel under pressure for controllingthe supply of fuel to the burner, and a master controller forcontrolling the supply of fuel under pressure for operating said fuelregulator, of a damper regulator for operating the damper and adapted tocontrol the flow of fuel under pressure from the master controller tothe fuel regulator.

6. In a liquid fuel burning apparatus, the combination with a fuelburner, a fuel regulator operated by fuel under pressure for controllingthe supply of fuel to the burner, and a master controller forcontrolling the supply of fuel under pressure for operating said fuelregulator, of a damper regulator having a piston operated by fuel underpressure for shifting the damper and valve means for controlling theflow of fuel under pressure from the master controller to said fuelregulator.

7. In a liquid fuel burning apparatus, the combination with a fuelburner, a fuel regulator operated by fuel under pressure for controllingthe Supply of fuel to the burner, and a master controller forcontrolling the supply of fuel under pressure for operating said fuelregulator, of a damper regulator operated by the flow of fuel underpressure from the master controller to the fuel regulator for operatingthe damper.

8. In a liquid fuel burning apparatus, the combination with a fuelburner, a fuel regulator operated by fuel under pressure for controllingthe supply of fuel to the burner, and a master controller forcontrolling the supply of fuel under pressure for operating said fuelregulator, of a damper regulator having a iston adapted to be actuatedby the flow 0 fuel under pressure from the master controller to the fuelregulator for controlling the movement of the damper.

9. In a liquid fuel burning apparatus, the combination with a fuelburner, a fuel regulator operated by fuel under pressure for controllingthe supply of fuel to the burner, and a master controller operated byboiler steam pressure for controlling the supply of fuel under pressurefor operating sai fuel regulator, of a damper regulator having means forfirst supplying fuel under pressure from the master controller to thefuel regulator and a piston operated by the flow of fuel under pressureto the fuel regulator for then operating the damper.

10. In a liquid fuel burning apparatus, the combination with a fuelburner, a fuel regulator operated by venting fuel under pressuretherefrom for opening the sup ly. of fuel to the burner, and a mastercontroller operated by a reduction in boiler steam pressure for ventingfuel under pressure from said fuel negulator, of a damper regulatorhaving a piston operated by venting fuel under pressure therefrom foropening the damper and valve means operated by said piston for openingcommunication for venting fuel under pressure from the fuel regulator tothe master controller.

11. In a liquid fuel burning apparatus, the combination with a fuelburner, a multiple stage fuel regulator operated by liquid underpressure for regulatin the fuel supply to the burner by steps, an amultiple stage master controller operated by variations in boiler steampressure for; varying the liquid pressure on said fuel regulator, of amultiple stage damper controller operated by liquid un er pressure foradjusting the damper by steps.

12. In a liquid fuel burning apparatus, the combination with a fuelburner, a plurality of fuel regulator units, each controlled by fuelunder pressure for varying the supply of fuel to the burner, and aplurality of master controller units, each governed by boiler steampressure for controlling the supply of fuel under pressure to thecorresponding fuel regulator unit, of a plurality of damper regulatorunits, each controlled by the How of fuel under pressure from one mastercontroller unit to the corresponding fuel regulator unit for varying theposition of the damper.

In testimony whereof we have hereunto set our hands' SHIRLEY S. WEEKS.

CARLTON D. STEWART.

Outlet of this patent my be obtained 10] an cents each, by addressingthe "Commissioner of Patents,

Washington, D. B."

